Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Recreational
APT. 5
MMSI 366745880 · Call sign WBR4490
Not yet on Master's MateType
Recreational
Flag
USALength
13.6 m
Beam
4 m
Draft
1.9 m
Call sign
WBR4490
Official No.
689433
AIS reports
1
APT. 5 flies the American flag — a 13.6-metre private vessel. Below, she has a 4-metre beam and a draft measuring 1.9 metres. Her papers read MMSI 366745880, call sign WBR4490. APT. 5 is invited to the free Master's Mate Safety Initiative Network, where cruisers keep each other safe.
Free forever · No credit card · for recreational captains
Keep APT. 5 looked after — even when you’re not aboard.
Anchor alarms that wake you, a live camera at the dock, and weather you can trust before every run.
Look after her — claim free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever APT. 5 roams, you're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
Free with your claim · for recreational captains
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put APT. 5 on the map. It hands you the full bridge:
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim APT. 5 and switch it all on
Free to join · nothing to install to start · cancel anytime
About APT. 5
What kind of vessel is APT. 5?
APT. 5 is a Recreational flagged to United States of America.
What is APT. 5's MMSI?
APT. 5's MMSI is 366745880. Call sign WBR4490.
How big is APT. 5?
APT. 5 is about 13.6 m long, 4 m on the beam, drawing 1.9 m.
Is APT. 5 on the Master's Mate Safety Initiative Network?
Not yet. If APT. 5 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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